AB0205 RA TREATMENT EFFECTS IN WRIST MRIS, DETERMINED BY DEEP LEARNING
Authors: T. Hassanzadeh, D. Shamonin, Y. Li, M. Reijnierse, A. Van der Helm – van Mil, B. Stoel
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Determining the response to early treatment of Rheumatoid Arthritis (RA) or the at-risk stages for RA from MRI scans requires sensitive and specific measurements of imaging biomarkers of inflammation. Employing artificial intelligence (AI), especially deep learning, can be an option to measure RA treatment effects. <h3>Objectives</h3> We aimed to assess the ability of deep learning to determine treatment response by distinguishing MRIs of the wrist between treatment and placebo arms (as proxy for treatment effects) from the TREAT-EARLIER trial. <h3>Methods</h3> Wrist MRIs (contrast enhanced T1-weighted TSE fat suppressed sequences) were collected from 236 patients with clinically suspect arthralgia at four time points (baseline, with 4, 12 and 24 months follow-up) to determine the response to treatment by intramuscular methylprednisolone followed by methotrexate during one year [1]. 3D wrist MRI data were reconstructed in super-resolution from axial and coronal images. Since a statistically significant treatment effect was determined previously y RAMRIS [1], we used these 3D wrist MRI data from baseline and after 4 months to classify patients into treatment arms by a 3D convolutional neural network. Five different inputs were explored for training the model: 1) a difference image (baseline image simply subtracted from follow-up); 2) the combination of baseline and follow-up image; 3) the combination of baseline and difference image; 4) change maps (AI-based maps containing changes between two time points); and 5) the combination of baseline and change maps (see bottom panel in Figure 1). To evaluate the proposed model, 10-fold cross-validation was repeated five times with five different splits, and the area under the receiver operator curve (AUC) was reported. <h3>Results</h3> The mean (<b>±</b>SD) AUCs are presented in Table 1. As shown, the combination of different MRIs obtained promising results. Specifically the combination of baseline images and AI-based extracted change maps could improve the accuracy. Compared to a setting where follow-up and baseline scans were simply 'subtracted', this improved the prediction of treatment from 0.72 to 0.76. <h3>Conclusion</h3> The results show that deep learning models using baseline and follow-up MRI specifically AI-extracted change maps can accurately determine treatment response in CSA patients. <h3>Reference</h3> [1]Krijbolder, DI, et al. "Intervention with methotrexate in patients with arthralgia at risk of rheumatoid arthritis to reduce the development of persistent arthritis and its disease burden (TREAT EARLIER): a randomised, double-blind, placebo-controlled, proof-of-concept trial." The Lancet 400.10348 (2022): 283-294. <h3>Acknowledgements</h3> This AI-project has been funded by the Dutch Research Council (NWO) Applied and Engineering Sciences (project number 17970). The TREAT-EALRIER trial has been funded by an NWO-ZonMW grant (project number 95104004). The Dutch Arthritis Society contributed financially to both grants. <h3>Disclosure of Interests</h3> Tahereh Hassanzadeh Grant/research support from: Bristol-Myers Squibb and Pfizer contributed to this project, through a grant from the Dutch Research Council (NWO), Applied and Engineering Sciences., Denis Shamonin Grant/research support from: Bristol-Myers Squibb and Pfizer contributed to this project, through a grant from the Dutch Research Council (NWO), Applied and Engineering Sciences., Yanli Li: None declared, Monique Reijnierse Grant/research support from: Bristol-Myers Squibb and Pfizer contributed to this project, through a grant from the Dutch Research Council (NWO), Applied and Engineering Sciences., Annette van der Helm – van Mil Grant/research support from: Bristol-Myers Squibb and Pfizer contributed to this project, through a grant from the Dutch Research Council (NWO), Applied and Engineering Sciences., Berend Stoel Grant/research support from: Bristol-Myers Squibb and Pfizer contributed to this project, through a grant from the Dutch Research Council (NWO), Applied and Engineering Sciences.